hayes



March 24, 1964 w g. HAYES 3,126,057

POSITION SELECTOR DEVICE FOR WELLS Filed Sept. 19, 1960 3 S sis-Sheet 1 23 INVENTORZ WILLIAM J. HAYES HIS AGENT FIG. 9

March 24, 1964 w. J. HAYES 3,126,057

POSITION SELECTOR DEVICE FOR WELLS Filed Sept. 19, 1960 5 Sheets-Sheet 2 FIG. 2

He 4 28 FIG 3 2e .INVENTQR:

WILLIAM J. HAYES 4/ 27 6- H.

HIS AGENT W. J. HAYES POSITION SELECTOR DEVICE FOR WELLS March 24, 1964 Filed Sept. 19, 1960 3 Sheets-Sheet 3 INVENTOR:

WILLIAM J. HAYES BY: HJ CMZQ.

ww ,9 I V 4 1:. if a 7. 4 53' 7 w M W 5 54 4 8 7 6 o 3 4 3 67 w m m a 4 ,6 w 55 J H- W 1A w 1. J 4/ ak I \S x 7 7. 1 4w 5 4 w. a 1 7 8 Q 5 5 5 HIS AGENT 3,126,657 POSlTIQN SELECTQR DEVICE FOR WELLS William J. Hayes, Houston, Tex assignor to Shell Gil Company, New York, Nil! a corporation of Delaware Filed Sept. 19, 196i Ser. No. 56,855 Claims. (Cl. 166-64) This invention relates to a well device adapted to be moved up or down a string of tubing positioned within a well and pertains more particularly to a device adapted to be purnped through a Well tubing together with a Well tool connected thereto whereby the tool may be seated at a predetermined position within the well. In addition to positioning tools at a predetermined position within a Well tubing, it is often desirable to position other well devices, instruments or equipment, for example gas-lift valves, etc.

A recent development in the oil industry is the drilling and completion of wells at an ofishore location where the wellhead assembly and production control units are positioned beneath the surface of a body of water and preferaoly close to the bottom of the body of water. With wellhead assemblies positioned on an ocean floor, a hazard to the navi ation of boats in offshore waters is removed. Additionally, considerable savings are realized in that it is not necessary to erect a protective stationary platform around the wellhead in the manner in which they are presently employed to protect well casing and wellhead assemblies extending above the surface of the Water. It has also been found necessary to position a wellhead on the ocean floor in water depths Where it is not feasible to erect a stationary platform around a wellhead assembly.

However, the placement of wellhead assemblies on the ocean floor raises a new set of problems with regard to carrying out workover operations, maintenance or other operations in a completed well. Major workover operations call for the use of a barge positioned on the surface of the water above the well together with equipment for going down and entering the wellhead assembly and the tubing or casing strings connected thereto, and in some circumstances may result in the entire removal of the wellhead assembly to the surface during workover operations. In order to carry out some of the more simple workover or maintenance operations, such as the perforation of well casing, the opening of a packer, the removal or insertion of a valve, the cleaning of paraffin from a tubing string, etc, it has been necessary to develop an entirely new line of well tools which can be pumped through a production tubing strhig from some remote location, oftentimes a mile or more from the well, and enter the well, passing down the tubing string therein to be subsequently positioned therein for carrying out some preselected operation. After completing the operation, the tool in the tubing string Within the Well is subsequently removed, generally by reverse circulation.

While the problem of pumping a tool to the bottom of a well tubing string in order to carry out certain operations is fairly readily solved, the problem of pumping a certain tool, device or other apparatus to a certain predetermined position within a well tubing is far more difficult. This is especially true in the event that it is necessary to position the tool or other device in one of a series of identical locations within a well tubing. Thus, for example, a well tubing may be provided with a series of gas-lift valves spaced at various intervals along the length of the tubing. In replacing gas-lift valves in a well tubing it is necessary to be sure to get the newly-positioned gaslift valve in the proper side pocket of the well tubing.

It is an object of the present invention to provide apparatus adapted to pass through a well tubing and automatically bypass a plurality of seating positions therein 3,126,057 Patented Mar. 24, 1954 until arriving at and subsequently being seated in a preselected position.

Another object of the present invention is to provide an apparatus adapted to be pumped through a string of pipe in a well and around curved portions thereof which may be located in and/ or outside a well, the apparatus being pumped together with a well device and subsequently being stopped at a preselected location in the pipe string.

A further object of the present invention is to provide apparatus adapted to pass through a well tubing and automatically seat itself in a preselected recess of a plurality of recesses spaced along a well tubing.

These and other objects of this invention will be understood from the following description taken with reference to the drawing, wherein:

FIGURE 1 is a schematic View illustrating a wellhead assembly positioned on the ocean floor;

FIGURES 2, 3 and 4 are diagrammatic views taken in longitudinal cross-section of a tubing string with the apparatus of the present invention positioned therein;

FIGURE 5 is a longitudinal view taken in cross-section of the position selector device of the present invention;

FIGURE 6 is a longitudinal cross-sectional view of the position selector device of the present invention taken at degrees to FIGURE 5;

Fl URE 7 is a cross-sectional view taken along the lines 77 of FIGURE 6;

FIGURE 8 is an expanded view of the clock mechanism employed in FIGURES 5 and 6; and,

FIGURE 9 is another form of a position selector device adapted to pass through the tubing string and selectively seat in a predetermined position therein.

Referring to FIGURE 1 of the drawing, a Wellhead assembly is shown as positioned below the surface 11 of a body of water and preferably on the ocean floor 12. The Wellhead apparatus comprises a platform 13 secured to the top of a conductor pipe or surface casing 14 which in turn extends into the earth below the body of water and is preferably cemented therein in a conventional manner. The wellhead assembly may also be provided with two or more vertically-positioned guide columns 15 and 16 which are fixedly secured at their lower ends to the platform 13. A well casinghead 17 is mounted on the top of the conductor pipe 14 with a control equipment housing 18 closing the top of the casinghead and/or any casing and tubing suspension equipment employed on the Wellhead assembly, as well as the various control valves and other control equipment normally used on the top of a well of this type.

Emerging from the housing 18 are a pair of flow lines 2%) and 21 which preferably bend in long sweeping curves from a vertical position down to a substantially horizontal position so that they can run along the ocean floor 12 to a remote location where fluid from the well, and normally from other Wells, is collected and metered and treated. Such a collection station may be several miles away. During the production of the well, normally only one of the flow lines 20 or 21 is employed in transporting fluid away from the well. The well may be provided with one or more strings of well casing 22 suspended within the conductor pipe 14. The flow lines 20 and 21 in the particular installation illustrated are in communication with a pair of tubing strings 23 and 24 depending within the well. However, in other well installations wherein a single tubing string is utilized, the second flowline may be in communication with the annular space between the tubing string and the adjacent well casing. For purposes of illustrating the apparatus of the present invention, one of the tubing strings 23 in FIGURE 1 is shown as being provided with a series of side pockets 25 in spaced relationship along the tubing string wherein gaslift valves may be positioned.

Referring to FIGURES 2, 3, and 4, it may be seen that the tubing string 23 is provided with suitable means for stopping a well tool or other device as it passes or is pumped through the tubing string. The stop means within the tubing string 23 may take the form of a recessed or expanded portion 26, for example, which is shown as having an internal diameter greater than that of the internal diameter of the tubing string 23. In the particular recessed portion 26 illustrated, a seating or stop shoulder 27 is formed at the bottom thereof while a tapered surface 23 is formed at the top thereof.

At a point near, and preferably above, the recessed portion 26 of the tubing string 23, a magnetized sleeve 31 of a diameter equal to that of the tubing string is connected into the tubing string 23. Arranged for sliding movement through the tubing string 23 is a well tool, device, instrument or other element 32, for example, a temperature indicating device which is designed to be positioned at a predetermined location in the tubing string, such for example as near the recessed portion 26. If it is desired that the instrument or tool 32 be pumped into position through the tubing string 23, a rubber motor swab element of a type described in copending application Serial No. 45,036, filed July 25, 1960, is provided. The motor swab cup 33 may be directly connected to the instrument or tool 32 or it may be connected to the position selector device 34 of the present invention which in turn is connected to the instrument or tool 32. Preferably, all connections 35 and 36 are in the form of flexible joints such as a short section of hose or a ball and socket joint whereby the connected elements may pass readily through curved sections of the tubing string 23. It is to be understood that the tubing string 23 may be provided with a plurality of the recessed portions 26 which may be spaced, say, several hundred feet apart.

The position selector device shown in FIGURES and 6 comprises a housing member 37 having a recess 38 formed therein near one end thereof in which a pair of latching dogs 41 and 42 are mounted on pivot pins 43 and 44 for radial expansion outwardly from the housing member 37 so as to contact the seating shoulder 27 of the recessed portion 26 of the tubing string 23 (FIG- URE 2). The outer faces of the lower portions 45 and 46 of the latching dogs 41 and 42 are preferably shaped at an angle so that when the latching dogs are in their extended position against the inner walls of a tubing string 23, the latching dogs 41 and 42 will readily pass over any joint formed between two sections of the tubing string without hanging up therein. A compression spring 47 is mounted between the latching dogs 41 and 42 for normally urging the latching dogs 41 and 42 outwardly. The latching dogs 41 and 42 are normally retained in a retracted or inoperative position, as illustrated in FIGURE 6, by any suitable means as by a pair of telescoping sleeves 50 and 51 which surround the spring 47. When the sleeves 50 and 51 are in their shortest telescoped position, a pair of holes through the sleeves are in register with each other allowing a pin 52 at the lower end of a slidable arm 53 to pass through the holes. Since each sleeve 50 and 51 is secured at one end to one of the latching dogs 41 and 42, the latching dogs 41 and 42 are prevented from moving outwardly as long as the pin 52 remains positioned in the holes in the sleeves 5t) and 51.

The arm 53 is slidably mounted for axial movement in bushings 54 and 55 centrally located within the housing member 37. A pin 56 through the arm 53 retains a compression spring 57 against lower bushing 55. A small-diameter pin 60 is formed at the end of the arm 53, the pin 60 being designed to fit into a slot 61 of an actuating wheel 62. The actuating wheel in turn is coupled to and is actuated by counting apparatus, such for example as a two-gear clock mechanism represented by a 12-tooth gear 63, an ll-tooth gear 64, a crank 65 and an indexing gear 66 in the expanded view of FIGURE 8.

Since two-gear clock mechanisms are well known to the art and are commercially available and do not constitute the novel portion of this invention, they will not be further described here.

The indexing gear 66 engages and is actuated by the lower end of the linkage arm 67. The upper end of the linkage arm 67 is connected through link 68 to a pivotable element 71, which contains a pair of magnets 72 and 73, and pivots around a pivot pin 74.

As shown in FIGURE 5, the magnet container ele ment 71 pivots between a pair of arms 75 and 76 within the housing member 37 which forms a frame that is connected together at the end by means of a rod 77. Although not essential, some suitable type of a locking device is employed to maintain the magnet carrier 71 in a normally-inoperative position. A suitable locking device may take the form of an L-shaped locking arm 80 pivoted on a pin 81 extending between the frame arms 75 and 76. A spring 82 is arranged to contact the locking arm normally to hold it in the position shown in FIGURE 6 with the horizontal part of the L substantially horizontal with the other end of the L limited in its movement by a stop element 83 against which the spring 82 may be positioned. The lower extending arm of the locking element 39 is provided with one or more magnets 84 while the upper edge of the locking arm is provided with a notch 85 into which one corner of the magnet carrier 71 latches, as shown in FIGURE 2 of the drawing. Since magnets 72, 73 and 84 are employed in the position selector device, the body element or housing member 37 and preferably any of the other elements of the device near the magnets are made of a nonmagnetic material. The magnets 72 and 73 Within the magnet container 71 are arranged so that identical poles of the magnets face outwardly, as illustrated.

Prior to running a tool, instrument or other device through a well tubing together with the position selector device of the present invention, a determination is made as to the depth to which the selector device 34 (FIG- URES 2 to 4) and its tool or instrument 32 are to be lowcred. For example, it may be decided that the indicator device 34 should be actuated at a time so that it seats itself in the fourth recessed portion 26 within the well tubing 23. In such a case, the actuating wheel 62 attached to the two-gear clock mechanism within the housing member 37 would be rotated backwards for the correct number of notches, in this case, four notches. The indicator device 34, together with its tool 32 attached thereto, would be put in an open end of the tubing string 23 and passed therethrough until it had reached the fourth recessed portion in the tubing string. Preferably, a motor swab 33 is attached to the position selector device 34 so that the entire assemblage, including the tool 32 and preferably another oppositely positioned motor swab (not shown) attached to the other end thereof, is put into a tubing string and the tubing string attached to a pump so that a fluid may be pumped down the tubing string 23 in back of the assembled elements 33, 34 and 32. As the assembled tool passes down the tubing string 23, it passes the series of magnetized sleeves 31 which are arranged in a manner so that identical poles of the magnetized sleeve are all positioned in the same direction, for example, the south poles on all of the sleeves would be the uppermost pole. Additionally, it is necessary that the uppermost pole or the pole first encountered by a tool as it passes down through the tubing string 23 is a pole which is opposite in character to the most outwardly extending poles of magnets 72 and 73 in the magnet container 71 and magnets 34 on the locking arm 80.

In FIGURES 2, 3 and 4, an assembled tool including the position selector device of the present invention is shown as passing down the tubing string 23. As the housing member 37 of the position selector device 34 passes downwardly past the upper end or south pole end of the magnetized sleeve 31, the magnets 84 on the locking arm 80 are attracted to the oppositely polarized upper end of the magnetic sleeve 31, thus causing the lower corner of the magnet carrier 71 to be released from the notch 85 in the locking arm 80. In its unlocked state the magnet container 71 is now able to pivot around pin 74. When the operating arm of the device comprising the pivotable element 71 and its magnets 72 and 73 reaches the upper arm of the magnetized sleeve 31, the magnets 72 and 73 are attracted to the oppositely polarized upper section of the magnetized sleeve 31 and cause the pivotal element 71 to rotate to a near horizontal position as shown in FIGURES 4 and 6.

As the position selector device continues to pass downwardly through the magnetized sleeve 31, the locking arm 80 and its magnets 84 comes opposite the similarly polarized lower section of the magnetized sleeve 31 at which time the magnets 84 are forced away from the tubing string and the locking arm is returned by means of spring 82 to its locking position as shown in FIGURE 6. As the magnets 72 and 73 pass downward through the lower end of the magnetized sleeve 31, they are also repulsed by the like polarization of the lower end of the magnetized sleeve 31 and are caused to return to the original vertical position. In returning to this position the linkage arm 67, which is operatively-connected to the gear clock mechanism, causes the mechanism to move one notch, i.e., the slot 61 in the actuating wheel 62 moves one notch closer to the pin 60 at the end of arm 53 that is adapted to slip into the slot 61. At the same time the locking arm 80 locks the pivotal element or magnet carrier '71 in its near vertical position as shown in FIGURE 2. The locking arm 80 is held in the locking position by the spring 82 which is strong enough to prevent the magnet inserts 84 from being pulled to the metal wall of the tubing as the entire tool is run through the tubing string 23. This spring is compressed when the magnet inserts pass through a magnetized sleeve 31.

The linkage arm is attached, as by ratchet to the indexing gear 66 which rotates the two-gear clock mechanism 6364 through an arc determined by the number of teeth on the ratchet gear. The two-gear clock mechanism in turn rotates the actuating wheel 62. When the tool has passed down the tubing string and has passed the predetermined number of magnetized sleeves 34, in this case four, the actuating wheel 62 is rotated to its correct position, in this case four notches, so that the releasing arm 53 is allowed to travel upward so that the pin 60 at the top thereof moves into the slot 61. Upward movement of this arm 53, which is caused by the spring 57, pulls the pin 52 out of the telescoping sleeves 5t and 51 so that they are allowed to be expanded by means of spring 47 which also forces the latching dogs 41 and 42 outwardly. These latching dogs 41 and 42 then move along the inner wall of the tubing string 23 (FIGURE 4) until they enter the recessed portion 26 thereof where they seat on shoulder 27. After the necessary operations have been carried out by the tool or instrument 32, the entire apparatus may be removed from the well tubing, as by circulating fluid down the outside of the tubing or down another tubing string and then upwardly through tubing string 23. In moving up through the tubing string 23 a motor swab (not shown) at the upper end of the tool, which is similar to motor swab 33 but in a reversed position, would act as the motor swab on the upward travel. The latching dogs 41 and 42 would be readily retracted into the housing member 37 and would have no tendency to hang up on the bevelled surface 28 of each of the recessed portions 26 in the tubing string 23.

While the position selector device of the present invention has been described with regard to pumping it down a tubing string having a plurality of recessed portions 26 therein together with an equal number of magnetized sleeves 31, it is evident that the same operation could be accomplished with the present equipment if there were one less magnetized sleeve than the number of recessed portions 26 employed in the tubing string. Thus, to position the selector device of the present invention in the first recessed portion 26 on its downward travel, the position selector device 34 may be run through the tubing string with the latching dogs 41 and 42 bearing against the inner wall of the tubing string without the releasing arm 53 locking the telescoping sleeves 50 and 51. Upon entering the recessed portion 26 the latching dogs would seat on shoulder 27.

In the event that it was desired to have the selector device seat in the second downstream recessed portion 26, the magnetized sleeve 31 could be positioned anywhere between the first and second recessed portions 26 and the two-gear mechanism of the selector device would be set back one notch so that it would release the latching dogs 41 and 42 after passing one recessed portion and one magnetized sleeve so that it would seat in the second re cessed portion. Although it is preferred that the tubing string 23 be provided with magnetized sleeves 31 for actuating the position selector device 34 of the present invention, it is to be realized that the position selector device may take another form, for example, a device 86 (FIGURE 9) having one or more outwardly extensible arms 37 adapted to move into the recessed portion 26 of the tubing string. Such movement away from the body of the device 86 is adapted to actuate the position selector device 86. Thus, no magnetized sleeves need be employed. Such a device is described in copending patent application Serial No. 67,647, filed November 7, 1960.

I claim as my invention:

1. Apparatus for selectively limiting the downward travel of a well device through a pipe string depending vertically within a well, said apparatus comprising a vertical pipe string, a plurality of recessed stop means of equal diametrical dimensions formed Within the pipe string at axially spaced locations therealong and adapted to be selectively engaged by a stepwise-actuatable position selector device passing through said pipe string, position-indicating and actuating marker means of equal diametrical dimensions carried by said pipe string each at a point intermediate adjacent stop means for stepwise actuation of a position selector device passing said marker means, a pumpable well device including a stepwise-actuatable position selector device of a diameter suflicient to pass through said pipe string and by said marker means therein to stop selectively at one of said stop means, latching means carried by said position selector device, latch actuating means carried by said position selector device and operatively connected to said latching means and responsive to movement past each of said marker means, a portion of said latch actuating means being adjustable timing and release means operatively connected to said latch actuating means for delaying the operation of said latch actuating means until said position selector device is in a preselected portion of said pipe string.

2. Apparatus for selectively limiting the downward travel of a well device through a pipe string depending vertically within a well, said apparatus comprising a vertical pipe string, a plurality of recessed stop means of equal diametrical dimensions formed within the pipe string at axially spaced locations therealong and adapted to be selectively engaged by a stepwise-actuatable position selector device passing through said pipe string, position-indicating and actuating marker means of equal diametrical dimensions in said pipe string each adjacent one of said stop means for stepwise actuation of a position selector device passing said marker means, the number of marker means in said pipe string being at least equal to the number of stop means less one, a pumpable Well device including a stepwise-actuatable position selector device of a diameter sufiicient to pass through said pipe string and by said marker means therein to stop selectively at one of said stop means, normally-retracted radiallyextensible latching means carried by said position selector device, latch actuating means carried by said position selector device and operatively connected to said latching means a portion of said latch actuating means being responsive to movement past each of said marker means, adjustable timing and release means operatively connected to said latch actuating means for delaying the operation of said latch actuating means until said position selector device is in a preselected portion of said pipe string.

3. A stepwise-actuatable position-selector device of a size adapted to pass through a pipe string in a well to a selected recessed portion thereof, said selector device comprising an elongated body member, radially-extensible latching means carried within said body member, latchactuating means carried by said body member and operatively connected to said latching means, a counter mech anism operatively connected to said latching means for actuating said latching means on arrival at a preselected position in a pipe string, and counter actuating means carried by said body member and operatively connected to said counter mechanism for stepwise actuation of said counter mechanism, said counter actuating means being actuatable by and responsive to movement past actuating marker means spaced along the pipe string through which said selector device moves to actuate stepwise said counter mechanism.

4. A stepwise-actuatable position-selector device of a size adapted to pass through a pipe string in a Well to a selected recessed portion thereof, said selector device comprising an elongated body member, spring-loaded normally-retracted radially-extensible latching means cmried within said body member, arm means in said body member and operatively connected to said latching means to hold said latching means normally in a retracted position, adjustable gear clock mechanism connected to one end of said arm means to actuate said arm means when said gear clock mechanism has arrived at a preselected position, and clock-actuating means carried by said body member and operatively connected to said clock mechanism for stepwise actuation of said clock mechanism.

5. A stepwise-actuatable position-selector device of a size adapted to pass through a pipe string in a well to a selected recessed portion thereof, said selector device comprising an elongated body member having a chamber formed therein, flexible tool joint connector means carried on at least one end of said body member for connecting a well device thereto, spring-loaded normally-retracted radially-extensible latching means carried within said body member, arm means in said body member and operatively connected to said latching means to hold said latching means normally in a retracted position, an adjustable gear clock mechanism connected to one end of said arm means to actuate said arm means when said gear clock mechanism has arrived at a preselected position, clockactuating means carried by said body member and operatively connected to said clock mechanism for stepwise actuation of said clock mechanism, said clock-actuating means being actuatable by and responsive to movement past actuating marker means spaced along the pipe string through which said selector device moves to actuate stepwise said counter mechanism.

6. A well apparatus through which a well device together with a position selector device may be passed and selectively engage one of a plurality of movement-limiting positions arranged in spaced relationship, said apparatus comprising a pipe string positioned within a well, a plurality of stop means of equal diametrical dimensions carried by said pipe string and adapted to be selectively engaged by a position selector device having a stepwise-actuatable latching means passing through the pipe string, and actuating marker means of equal diametrical dimensions carried by said pipe string for actuating stepwise said position selector device latching means as it passes thereby on movement through the pipe string.

7. A well apparatus through which a Well device together with a position selector device may be passed and selectively engage one of a plurality of movement-limiting positions arranged in spaced relationship, said apparatus as it passes thereby on movement through the pipe string.

8. A Well apparatus through which a well device together with a position selector device may be passed and selectively engage one of a plurality of movement-limiting positions arranged in spaced relationship, said apparatus comprising a pipe string positioned within a well, a plurality of stop means formed on the inner wall of said pipe string and adapted to be selectively engaged by a stepwiseactuable position selector device passing through the pipe string, and actuating marker means carried by said pipe string at least between each two stop means for actuating stepwise said position selector device as it passes thereby on movement through the pipe string, said actuating marker means being in the form of magnet means carried by said pipe string, the poles of said magnet means being aligned parallel to the axis of said pipe string with similarly polarized portions of said magnet means being similarly directed.

9. Apparatus for selectively limiting the downward travel of a well device through a pipe string depending vertically within a well, said apparatus comprising a vertical pipe string, a plurality of stop means of equal diametrical dimensions formed within the pipe string at axially spaced locations therealong and adapted to be selectively engaged by a stepwise actuatable position selector device passing through said pipe string, position indicating and actuating marker means of equal diametrical dimensions carried by said pipe string each at a point intermediate adjacent stop means for stepwise actuation of a position selector device passing said marker means, a pumpable well device including a stepwise actuatable position selector device of a diameter suflicient to pass through said pipe string and by said marker means therein to stop selectively at one of said stop means, and latching means carried by said position selector device being stepwise actuatable for selectively latching at a selected stop means.

10. Apparatus for selectively limiting the downward travel of a well device through a pipe string depending vertically within a well, said apparatus comprising a vertical pipe string, a plurality of stop means of equal diametrical dimensions formed within the pipe string at axially spaced locations therealong and adapted to be selectively engaged by a stepwise actuatable position selector device passing through said pipe string, position indicating and actuating marker means of equal diametrical dimensions carried by said pipe string each at a point intermediate adjacent stop means for stepwise actuation of a posin'on selector device passing said marker means, a pumpable well device including a position selector device of a diameter suflicient to pass through said pipe string and by said marker means therein to stop selectively at a selected stop means, latching means carried by said position selector device, and latch actuating means carried by said position selector device and operatively connected to said latching means, a portion of said latch actuating means being stepwise actuatable responsive to movement past each of said marker means.

References Cited in the file of this patent UNITED STATES PATENTS 2,810,440 Kenneday et al Oct. 22, 1957 2,862,564 Bostock Dec. 2, 1958 2,927,641 Buck Mar. 8, 1960 2,942,462 Buck June 28, 1960 

1. APPARATUS FOR SELECTIVELY LIMITING THE DOWNWARD TRAVEL OF A WELL DEVICE THROUGH A PIPE STRING DEPENDING VERTICALLY WITHIN A WELL, SAID APPARATUS COMPRISING A VERTICAL PIPE STRING, A PLURALITY OF RECESSED STOP MEANS OF EQUAL DIAMETRICAL DIMENSIONS FORMED WITHIN THE PIPE STRING AT AXIALLY SPACED LOCATIONS THEREALONG AND ADAPTED TO BE SELECTIVELY ENGAGED BY A STEPWISE-ACTUATABLE POSITION SELECTOR DEVICE PASSING THROUGH SAID PIPE STRING, POSITION-INDICATING AND ACTUATING MARKER MEANS OF EQUAL DIAMETRICAL DIMENSIONS CARRIED BY SAID PIPE STRING EACH AT A POINT INTERMEDIATE ADJACENT STOP MEANS FOR STEPWISE ACTUATION OF A POSITION SELECTOR DEVICE PASSING SAID MARKER MEANS, A PUMPABLE WELL DEVICE INCLUDING A STEPWISE-ACTUATABLE POSITION SELECTOR DEVICE OF A DIAMETER SUFFICIENT TO PASS THROUGH SAID PIPE STRING AND BY SAID MARKER MEANS THEREIN TO STOP SELECTIVELY AT ONE OF SAID STOP MEANS, LATCHING MEANS CARRIED BY SAID POSITION SELECTOR DEVICE, LATCH ACTUATING MEANS CARRIED BY SAID POSITION SELECTOR DEVICE, LATCH AND OPERATIVELY CONNECTED TO SAID LATCHING MEANS AND RESPONSIVE TO MOVEMENT PAST EACH OF SAID MARKER MEANS, A PORTION OF SAID LATCH ACTUATING MEANS BEING ADJUSTABLE TIMING AND RELEASE MEANS OPERATIVELY CONNECTED TO SAID LATCH ACTUATING MEANS FOR DELAYING THE OPERATION OF SAID LATCH ACTUATING MEANS UNTIL SAID POSITION SELECTOR DEVICE IS IN A PRESELECTED PORTION OF SAID PIPE STRING. 